The improve-relatime.patch is enabled in the Fedora 9 kernel, but not in Fedora 10:
# cat /proc/mounts | grep relatime | wc -l
This is the patch:
More info on how this patch would improve performance:
Version-Release number of selected component (if applicable):
Merged upstream, and backported to Fedora 10, Fedora 11 and Rawhide:
Fedora 11 will have relatime as default, Fedora 10 won't have it as default, but will support it.